Our Roybal Center is focused on the recognition that complex social network structures play an important role in individual health. The two overarching goals of our work are (1) to ask significant questions about the role of social networks in producing specific outcomes related to health and well-being, and (2) to develop methods of answering such questions involving real social networks in which behavioral information relevant to health and well-being can be measured. Our Roybal Center will focus on the social network underpinnings of some of the most pressing problems facing the health and well-being of the elderly in the U.S. today, such as obesity and cancer, using a variety of novel methods applied to populations of diverse ages. Our Center will emphasize the use of internet data collection and the experimental manipulation of network properties; in addition, we also expect to continue to exploit our extant data, including our unique Framingham Heart Study Social Network. We will examine the impact of the topology and dynamic functioning of social networks. We will examine both inperson and online social networks for the effects of patterns of interpersonal network connections on health and well being, and we will study how health and well being are affected by the flow of phenomena across network ties. Our specific aims are to: (1) create a Center that contributes to the development of new methods for understanding social network effects on health in new areas, (2) fund pilot projects that examine how network topology, particularly in online social networks, affects health and well-being, (3) fund pilot projects that examine how the flow of health behaviors and states through network structures occurs in both real life social networks, such as the Framingham Heart Study Social Network, and in online networks, (4) help translate the findings of pilot projects into concrete recommendations for helping people improve health behaviors and well being, (5) help translate the findings of pilot projects and other social network research into policy recommendations for government and other stakeholders, (6) broadly promote and coordinate research with our separate social networks-focused Program Project on issues related to health and well being in the elderly.